Fix crash on playback error

vlc-android/src/org/videolan/vlc/PlaybackService.java

@@ -520,9 +520,6 @@ public class PlaybackService extends MediaBrowserServiceCompat{
                     executeUpdateProgress();
                     break;
                 case MediaPlayer.Event.EncounteredError:
-                    showToast(getString(
-                            R.string.invalid_location,
-                            playlistManager.getCurrentMedia().getLocation()), Toast.LENGTH_SHORT);
                     executeUpdate();
                     executeUpdateProgress();
                     break;

vlc-android/src/org/videolan/vlc/media/PlaylistManager.kt

@@ -665,7 +665,12 @@ class PlaylistManager(val service: PlaybackService) : MediaWrapperList.EventList
                     next()
                 }
             }
-            MediaPlayer.Event.EncounteredError -> next()
+            MediaPlayer.Event.EncounteredError -> {
+                service.showToast(service.getString(
+                            R.string.invalid_location,
+                            getCurrentMedia()?.getLocation() ?: ""), Toast.LENGTH_SHORT)
+                next()
+            }
         }
         service.onMediaPlayerEvent(event)
     }